Taking that logic to it's ultimate conclusion, why would anyone choose to support any team other than Man City / Man U / Chelsea / Liverpool? If bigness and success are the criteria for selecting a team to support, I don't think the scum over the river would enter anyone's calculations. Thankfully, some people see beyond that, and support the team that they love for whatever reason. One thing I've realised over the years is that one diehard supporter of a struggling lower league club is usually worth 10 'big club' supporters.